Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Fokker Model F28 Mark 0100 series airplanes. This proposal would require replacement of the return filter diaphragm assemblies on hydraulic systems 1 and 2 with modified filter units having new diaphragms. This proposal is prompted by a report of insufficient running clearance of the brake units due to overpressure in the hydraulic return system; this condition could lead to brake overheating. The actions specified by the proposed AD are intended to prevent overpressure of the hydraulic return system, which could result in reduced braking performance and/or blown tires due to brake overheating.